Preserving white lines in cartoon when denoising

[starplayer]

Hi guys.
I'm trying to denoise some very old cartoons, to reduce the file size.
It's working quite nice, reducing the file size to about a fifth of the original, but the thing is there are some white lines that are disappearing too much. Check the boots on the picture:
Original

Denoised


I'm using fft3dgpu as it's fast with
Sigma:3; Sharp:1; Block 16/16/3; Precision: 2

My settings:
x264 --crf 20.00 --profile high10 --direct auto --b-adapt 0 --qcomp 0.5 --qpmax 81 --partitions i4x4,p8x8,b8x8 --no-fast-pskip --subme 5 --trellis 0 --weightp 1 --aq-mode 0 --sar 1:1 --qpfile GENERATED_QP_FILE --non-deterministic --range tv --colormatrix bt709 --demuxer raw --input-res 1920x1080 --input-csp i420 --input-range tv --input-depth 10 --fps 24000/1001 --output-depth 10 --output "C:\Users\Rafael\AppData\Local\Temp\FullCamouflage .264" -

Any ideas on how to get better definition on those white lines while maintaining the overal denoising?

[johnmeyer]

ff3d is a nice denoiser, but it does tend to soften details. A temporal denoiser might give you sharper results.

[jagabo]

Yes, use a temporal only denoiseer. Especially one with motion compensation (much better for panning shots). Or use no denoising at all. Just use a high bitrate to retain the noise and detail.

[Cornucopia]

Every time I hear claims like "1/5th of the original" I have to roll my eyes.

@starplayer, Maybe you don't realize it, but the "original" is probably not 5x your size but more like 270x your size. You are just doing 1/5 on something which was already shrunk to 1/54. Piling on the damage.

Scott